local ABILITY_ID = AbilityId('SBls')
local BUFF_ABILITY_ID = AbilityId('ABls')
local BUFF_ID = AbilityId('BBls')
local AURA_ID = AbilityId('PBls')
local DURATION = {10, 15, 20}

//! beginusercode
do
    -- На момент патча 1.31 эта функция всегда возвращает 0. Поэтому создадим её локальный аналог.
    local function AbilityId(id)
        return id:byte(1) * 0x1000000 + id:byte(2) * 0x10000 + id:byte(3) * 0x100 + id:byte(4)
    end

    -- Настройки
    local ABILITY_ID = AbilityId('SBls')
    local BUFF_ABILITY_ID = AbilityId('ABls')
    local BUFF_ID = AbilityId('BBls')
    local AURA_ID = AbilityId('PBls')
    local DURATION = {10, 15, 20}
    
    -- Заклинание
    local DAMAGE_TRIGGER = CreateTrigger()
    local DAMAGE_GROUP = CreateGroup()

    TriggerAddAction(DAMAGE_TRIGGER, function()
        if GetUnitAbilityLevel(GetTriggerUnit(), BUFF_ID) == 0 then return end
        BlzSetEventDamage(0)
    end)

    local t = CreateTrigger()
    for i = 0, bj_MAX_PLAYER_SLOTS - 1, 1 do
        TriggerRegisterPlayerUnitEvent(t, Player(i), EVENT_PLAYER_UNIT_SPELL_EFFECT)
    end
    TriggerAddCondition(t, Condition(function()
        return GetSpellAbilityId() == ABILITY_ID
    end))
    TriggerAddAction(t, function()
        local caster = GetTriggerUnit()
        local target = GetSpellTargetUnit()
        local level = GetUnitAbilityLevel(caster, ABILITY_ID)
        local damage = BlzGetUnitBaseDamage(caster, 1) * level
        UnitAddAbility(caster, BUFF_ABILITY_ID)
        if not IsUnitInGroup(caster, DAMAGE_GROUP) then
            TriggerRegisterUnitEvent(DAMAGE_TRIGGER, caster, EVENT_UNIT_DAMAGING)
            GroupAddUnit(DAMAGE_GROUP, caster)
        end

        UnitAddAbility(caster, AURA_ID)
        SetUnitAbilityLevel(caster, AURA_ID, level)

        TimerStart(CreateTimer(), DURATION[level], false, function()
            UnitRemoveAbility(caster, BUFF_ID)
            UnitRemoveAbility(caster, BUFF_ABILITY_ID)
            UnitRemoveAbility(caster, AURA_ID)
            DestroyTimer(GetExpiredTimer())
        end)
    end)
end
//! endusercode